# CVE-2026-77609: Semantic MediaWiki open redirect in Special:URIResolver

Source: https://junglewise.ai/threats/cve-2026-77609-semantic-mediawiki-open-redirect-in-special-uriresolver  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-18. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-77609 · Severity: medium · CVSS 6.1 · Published 2026-09-18

Semantic MediaWiki is a semantic layer for MediaWiki that extends its capabilities with structured data. The Special:URIResolver page contains an open redirect vulnerability that allows attackers to craft URLs appearing to originate from a trusted wiki but actually redirecting to attacker-controlled hosts. This can be used for phishing attacks against wiki users and staff.

Technologies: [mediawiki/semantic-media-wiki (Packagist)](https://junglewise.ai/threats/technologies/mediawiki-semantic-media-wiki), [Semantic MediaWiki](https://junglewise.ai/threats/technologies/semantic-mediawiki). Vendors: [Packagist](https://junglewise.ai/threats/vendors/packagist), [Semantic MediaWiki](https://junglewise.ai/threats/vendors/semantic-mediawiki).

## Quick answers

**Is CVE-2026-77609 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-77609 being exploited in the wild.

**How severe is CVE-2026-77609?** Medium severity, with a CVSS score of 6.1, published 18 September 2026.

**Which products and versions are affected?** mediawiki/semantic-media-wiki (Packagist) <= 7.1.0, ECOSYSTEM:introduced=0,fixed=7.2.0; Semantic MediaWiki <= 7.1.0.

**Is there a fix for CVE-2026-77609?** Yes. mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-77609 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-77609?** Check whether you run mediawiki/semantic-media-wiki (Packagist) or Semantic MediaWiki at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- mediawiki/semantic-media-wiki (Packagist): upgrade to 7.2.0 or later

  ```sh
  composer require mediawiki/semantic-media-wiki:^7.2.0
  ```


## Technical details

The vulnerability is an open redirect (CWE-601) in the Special:URIResolver page. The vulnerable component processes user-controlled subpage parameters and resolves them to MediaWiki titles, then issues an HTTP 303 redirect to the resolved URL without validating the target host. An attacker can craft a URL using interwiki prefixes (e.g., mw-3AFoo decoding to mw:Foo) or embed credentials (user:pass@host) to redirect to off-host destinations. The attack requires user interaction (clicking the link) and is network-accessible without authentication. The patch validates the resolved target URL and host matches against the current host before issuing the redirect.

## Affected products

- Semantic MediaWiki Semantic MediaWiki <= 7.1.0

## Identifiers

- CVE-2026-77609
- GHSA-hw3m-8j5x-94ff

## Timeline

- 2026-09-18: disclosed
- 2026-09-18: patched: Version 7.2.0 patches the vulnerability

## References

- [https://api.github.com/users/krabina](https://api.github.com/users/krabina)

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- [Semantic MediaWiki missing authorization in page edit protection](https://junglewise.ai/threats/cve-2026-126561-semantic-mediawiki-2-5-0-before-7-4-1-contains-a-missing)